Drifting valve



April 1930- D, T. WILLIAMS 1,752,321

DRIFTING VALVE Filed Dec, 51, 1925 2 Sheets-Sheet 1 1 y 3 6" g G L .L'="J WITNESS WQ DawdLIWnhams I I v ATTORNEY D. T. WILLIAMS DRIFTING VALVEApril 1, 1930.

, 1925 2 Sheets-Sheet 2 Filed Dec. 31

ATTORNEY Patented Apr. 1, 1930 UNITED STATES DAVID T. WILLIAMS, OFEATER/SON, NEW JERSEY DRIFTING VALVE" Application filed December a1,1925'; Serial No. 78,567. i

' This invention relatesto automatic means whereby, when the drivingsteam is cut E from alocomotive engine, fluid, as boiler steam, is"admitted to the engine, and when the drivingsteam is allowed to flow tothe engine'the flow of such fluid is checked, so

that under the first of these conditions the known disadvantageousresults ofthe piston continuing to reciprocate in vacuo inithe en- '10gine cylinder will be avoided. The object is to -provide improved meansof this class, or what is known as an automatic drifting valve, whichshall embody 'all ofthe following advantageous features, to wit,efliciency 1 under allconditions, simplicity of construc-' tion,andreliability not only in} respect to the performance of its principalfunction but to the-end that its incorporation in the equipment of alocomotive shall not introduce any 2 possible element of danger I havefully illustrated my invention in the accompanying drawings,-in whichFig. 1- is aside View of alocomotive embodying the" improved driftingvalve Fig. 2 is a fragmentary rear elevation of th'e'boiler', steamturret and one of the-steam pipes; and g Figs-3 and 4 are avertical'c'entral sectional view and an, end view of the device. Thelocomotive has an engine of usual type,

1' being the cylinder and 2'the steam-chest;

3 is" the main" steam pipe for super heated steam leading to thesteam-chest, and 4 is" a steam turret communicating with the" boiler 5andconveniently placed" as usual in the drivers cab. i

I The drifting valve is indicated generally in- Fig. 1 by the character6: The pipe through which control of the moving'part of thisdriftingvalve is eifected from the steam-chest (or'rather all thatspace, which I termthe working space, which is subject to thesuction-action of the piston in said cylinder when the locomotive isdrifting with thedriving steam cut off) is indicated at 7 it may have ashut-offcock 7 The passage to'be'controlled (i. e., forfiuid,assaturated steam, which is to beadmitted to the locomotive cylinderwhen thelocomotive is driftingwith the driving steanrcutofi) isaffordthe source 4,- which communicates with the" ed by the pipe8,acylinder (tobe described-) of the drifting valve 6, and a-pipe 9; pipe8 leads fromthe turret 4 to the drifting valve and maycontain a reducingvalve 8 (Fig.2),

and pipe 9 leads from the drifting! valve to 5 any part of the mentionedworking space, as the main' steam pipe 3, and it may if desired containa check-valve 9 the detail of which is not shown and which it is notmaterial to describe except to say that it closestoward thedriftingvalve' It is neither necessary nor desirable,of course, thatth'e steam'pass ing to the locomotive'cylinder via 8-13''9' shouldhave apressure as great as that at boiler; hence the reducing valve 8 is provid'edz The casing or fixed part of the drifting valve includes a'hollow structure 10 having a base 11 and forming two cylinders 12 an'd13 axially" a lined with and open toward each other,-the' former (orwhat-I term the major cylinder) being ofappreci'ably greatercrosssectional areathanthe latter (0rminor) cylinder; and heads'l t and1-5bolted' to the outer ends of cylinders 1 2- and 13, there being a"space or chamber- 12* between-the cylinders. The moving member of thedeviceincl-udes' a major pisto'n-16-fitting cylin'der'lflganaxial stem17- suitably secured to said"-pistolr,- and an element here formed intwo parts 18 and- 19 with a'spa'ce or deep groove 'l e between them,they being suitably secured to the stern; and part 18 forminga valve tocontrol the aforementioned passage." The or cylin der piston iii-effectform a'moto'r forsueh valve: VV'heir' the locomotive engine is workingthe pressure in its mentioned working space actsthrough a port7 withwh-ic'h-pipe' 7 communicates to hold themoving member of the driftingvalve with piston 16 against a stop fiange l6 'an'd hence th'e valve'i rclosing relation to the passage; when the docomotive'engineis drifting,asthe result of the suction developed in said-working space, said movingmember is shifted to the left,-so that valve 18' uncovers the passagefrom 8 0 9 via space 19 and said passage is open and boiler steam flowstos'aid working s ace.

Piston 16 ha's a port 20 c0nnectingchamber as suction is created (ondrifting) in the working space of the engine, with consequent reductionof pressure at the left of piston-16,

and since the pressure area of piston 16 ex:

ceeds that of the valve portion of element 1819, the pressure in chamberl2 is effective to and does produce a ce tain and quick movement of thesaid moving member to open "the communication from 8 to 9. There ispreferably a vent 23 connecting the outer end of cylinder 13 with theatmosphere; it maybe suitably restricted so that the movement ofthemovable memberof the device in each'direction will be cushioned. Astandardizing of -the resistance opposed to the right-hand orvalve-closing movement of the moving member is obtained by providing avent 24: which is closed by piston 16 on such movement but is opened tothe atmosphere when said member moves to the left; this vent, and a port25 in stop-flangel6e also permit draining chamber 12 of anycondensation.t

Valve 18 is cup-shaped, with its open side toward part 19, and itscylindrical wall has radial ports 26 therethroughcommunicating with anexterior circumferential groove 27 whichwhen the valve is closedregisters with a vent 28 leading to the atmosphere.

The action of the device is both quick and certain, not only in themovement to close the passage afforded by 813 9 but in the movement toopen the same, due to the trapping of steam'from the working space ofthe engine in the chamber 12 and to the superior area of piston 16 overthat ofthe valve portion of the element '1819 taken with the existenceat this time of suction at the left side of the piston.

back through pipe 7 to cylinder space 12 would act to move said memberto close off the passagebefore the pressure would build up in theworkingspace -of the engine sufiicient to start the same. There will be aventing at 28 of steam entering the casing from said passageif, themoving member being in closed position, there is a leaky condition ofthe part 18, for instance, if thisis due to longitudinal scoring of saidpart-so that the leakclosed position the pressure at the right of part18 is not a resisting force because parts 1 9-1S then trap thispressure.

serve to vent this pressure at the end of the closing movement ofsaidmember.

Any condensation which at times might form in pipe 8 when the valve isclosed may find escape into space 19. by port 29, this port being smallenough so that the escape of steam therethrough and to space 19 andthence via 19 18 -262728 to the at mosphere would be negligible. r v

Having thus fully described my invention Regardless I of the pressure ofthe part 19, 18 262728 what I claim and desire to secure by Letters jPatent is: V

1. A drifting valve device for locomotive engines incrudiug a cylinderhaving an eduction port in its cylindricalwallforming with said cylindera part of a passage for conducting fluid to the working space of theengine while the locomotive is drifting and a valve movable lengthwiseof andin the cylinder to close ofi said passage, said-device havingmeans for venting from the cylinder fluid entering the latter when theyvalve is closed including a groove surrounding the valve at one sideofsaid eduction port and:

a passage extending from said groove to the end of thevalve-at'the otherside of said port. 7

2. Ina drifting valve device for locomotive engines, the combination ofa passaged structure for conducting steam tothe work ing space of theengine includinga cylinder, and a valve movable in the cylinder to close0E from the latter the part of the passage leading thereto, said devicehaving means, closed by the valve when the latter is open and extendingthrough the valve, f ,r venting to the atmosphere when the valve isclosed condensation then accumulating in said part of the passage. 7

3. In an apparatus of the class described, the combination of a casinghaving alined major and minor cylinders and achamber intervening betweenthem and communicating with'the major cylinder, the minor cyl-' inderhaving an inlet adapted to be connected with a steam source and anoutlet adapted to be connected with a locomotive steam chest, a pistonin the major cylinder, a valve in the minor cylinder to controlsteamfiow through the latter from the inlet to the outlet, said pistonand valve being movable longitudinally of the cylindersas a unit andthemajor cylinder having its outer end closed and also having an inlet toadmit fluid fromthe steam chest to the space between said end and thepiston whereby to move the latter and hence the valve in one direction,a check-valve means to permit a part of the fluid entering said spacefrom the steam chest to pass the piston and enter and become trapped insaid chamber, and means to vent said chamber on exhaust of the fluidfrom said space and consequent return movement of said piston and valve.V

In testimony whereof I aflix my signature.

DAVID T. WILLIAMS.

